special dermal puncture collections and procedures

• bilirubin - very light-sensitive chemical and is rapidly destroyed when exposed to light.
• hyperbilirubinemia - increased serum bilirubin
• hyperbilirubinemia - may be caused by the presence of hemolytic disease of the newborn or it may simply occur because the liver of newborns is often not developed enough
• Bilirubin test results - are critical to infant survival and mental health
• The decision to perform an exchange transfusion is based on the bilirubin levels and the newborn’s age and condition.
• Phlebotomy technique is critical to the determination of accurate bilirubin results, and samples must be collected quickly and protected from excess light during and after the collection.
• Infants who appear jaundiced are frequently placed under an ultraviolet light (UV) to lower the level of circulating bilirubin.
• UV light must be turned off during sample collection
• Amber-colored microcollection tubes are available for collecting bilirubin, or if multiple capillary pipettes are used, the filled tubes should be shielded from light.
• Hemolysis must be avoided; it will falsely lower bilirubin results in some procedures and must be corrected for in others.
• samples must be collected at the specified time so that the rate of bilirubin increase can be determined
• When collecting samples for neonatal bilirubin tests, turn off the ultraviolet light during collection unless it is a newer model that is strapped directly to the infant.
• Bilirubin levels may decrease as much as 50% in a blood sample that has been exposed to light for 2 hours
• Newborn screening - the testing of newborn babies for genetic, metabolic, hormonal, and functional disorders that can cause physical disabilities, mental retardation, or even death, if not detected and treated early.
• Screening of newborns for 50 inherited metabolic disorders can currently be performed from blood collected by heelstick and placed on specially designed filter paper
• Many of these disorders can be prevented by early changes in the newborn’s diet or early administration of a missing hormone. Examples of the common disorders phenylketonuria (PKU), congenital hypothyroidism, and galactosemia
• Newborn screening tests are performed on blood collected by dermal puncture, except for the hearing test.
• Ideally blood is collected between 24 and 72 hours after birth, before the baby is released from the hospital.
• It is recommended that the newborn screening samples should be collected separately, after prewarming and puncturing a second site when additional blood tests are requested.
• The phlebotomist must be careful not to touch or contaminate the area inside the circles or to touch the dried blood spots.
• phenylketonuria - caused by the lack of the enzyme needed to metabolize the amino acid phenylalanine
• phenylketonuria - accumulates and causes problems with brain development and mental retardation
• early detection of phenylketonuria is crucial because the damage is irreversible but can be treated with a diet low in phenylketonuria and high in tyrosine
• Congenital hypothyroidism - a thyroid hormone deficiency present at birth
• congenital hypothyroidism - delays in growth and brain development that produce mental retardation can be avoided by the use of oral doses of thyroid hormone within the first few weeks after birth
• Galactosemia - a genetic metabolic disorder caused by the lack of the liver enzyme needed to convert galactose (sugar in milk) into glucose
• galactosemia - Galactose accumulates in the blood and can cause liver disease, renal failure, cataracts, blindness, mental retardation, and death.
• galactosemia - treatment of this is the elimination of all milk and dairy products from the infant for life.
• heelstick - performed in the routine manner, and the first drop of blood is wiped away
• To prevent cross-contamination, samples should not be hung to dry or stacked during or after the drying process.
• When dry, the sample is placed in a special envelope and sent to the appropriate laboratory for testing.
• Be sure that all required patient information is filled out on the neonatal screening test form.
• Uneven or incomplete saturation of filter paper circles because of layering from multidrop application will yield an unacceptable sample for testing.
• Specific state mandates for newborn screening can be found at the U.S. National Newborn Screening and Genetics Resource Center website
• Blood spots must be thoroughly dry before the attached fold-over flap is closed over the spots.
• Arterial blood - the preferred sample for blood gases (oxygen and carbon dioxide content) and pH levels in adults
• Performing deep arterial punctures in newborns and young children is usually not recommended
• blood gases - are performed on capillary blood
• Blood is collected from the plantar area of the heel or big toe and the palmar area of the fingers
• capillary blood is actually a mixture of venous and arterial blood, with a higher concentration of arterial blood.